Diseases of the retina and choroid are the major cause of severe vision loss in the Western Hemisphere. In many of these diseases one of the most severe complications includes new vessels, which hemorrhage, and often lie beneath the retina, as in age-related macular degeneration. Pathology that may precede visual loss can also lie beneath the retina, as is the case with deposits found in the aging eye, which may indicate risk of age-related maculopathy. In this proposal, we present a plan to improve the sub-retinal imaging capabilities of an important new ophthalmic diagnostic instrument, the Scanning Laser Ophthalmoscope (SLO). We will add to the SLO a recently developed, near-infrared, tunable solid state laser, which will allow fine control of the penetration of light below the retinal surface and allow viewing of structures previously unobserved in vivo. The program will include both laser development and a series of human experiments at the Schepens Eye Research Institute. The long-term goals of the program include a better understanding of retinal imaging with infrared light and the development of a commercial laser product that can be added to existing or future SLO systems.